2003 SSANGYONG MUSSO sport bar

1A-4 MUSSO-SPORTS
SUPPLEMENT
from vacuum pump
EGR valve
EGR control unit
KAA5A020
KAA5A020
KAA5A020
KAA5A020 EGR COMPONENTS EGR Unit
1. Location: behind passenger's side panel
2. Arrangement: 81-pin connector
3. Integrated self-diagnostic function (Scan-100: not
fixed)
4. Part number For automatic transmission: 28800-07100 For manual transmission: 28800-07000
Vacuum Modulator
1. Location: in front of intake manifold
2. Continuous precise control with the signals from EGR unit (PWM-Pulse With Modulation Control)
3. Rated voltage: 12 V
4. Operating voltage: 8 ~ 16 V
5. Resistance (at 20 °C): 15.4 ± 0.7
6. Operating range of vacuum (Duty control)


 Vacuum modulator 1: 0 ~ 600 mbar


 Vacuum modulator 2: 300 ~ 600 mbar
7. Modulator control


 Vacuum modulator 1: for controlling EGR valve


 Vacuum modulator 2: for controlling no-load sharp
acceleration (ALDA control)
not used connector
Vacuum modulator 1
(for controlling EGR valve)Vacuum modulator 2
(for controlling ALDA)
from vacuum pump
Vacuum modulator 1
Vacuum modulator 2
Solenoid valve
ALDAIntake
manifold
EGR control unit

MUSSO-SPORTS 1A-5
SUPPLEMENT
KAA5A020
KAA5A020
KAA5A020EGR Valve and Lift Sensor
1. EGR valve: The output signals from EGR unit controls
the vacuum modulator 1 through step 1 to step 16 precisely, accordingly the opening value of EGR valvewill be changed.
2. Lift sensor (potentiometer): EGR unit converts the position of EGR valve into electrical signal to detectthe opening value of the valve (Lift sensor). In additionto, this compensates the opening value of EGR valveby controlling the vacuum modulator 1 when thereare some differences between the output signal fromvacuum modulator 1 and the input value ofpotentiometer from EGR valve. If the closing or opening value EGR valve is different from the output value due to the carbon and paticlematerial in exhaust gas, the opening value of EGRvalve is compensated by adjusted the vacuum levelof vacuum modulator.
Measured EGR valve opening value Step 1 2
Vacuum(mbar)
approx. -370 approx. -690 Valve opening
value (mm)
approx. 0.2approx. 6.0 Output
voltage (V)
approx. 1.7 ~ 2.1
approx. 9.6 ~ 11.6
1. The opening value of the valve is the internal moving distance of EGR valve by vacuum pressure. The valve starts to move when the vacuum pressurereaches approximately -370 mbar. If the EGR valveis fully opened, the moving distance will be 6 mmdue to -690 hpa of vacuum pressure.
2. The output voltage may vary according to the battery voltage in vehicles. These values have been convertedinto percentage from battery voltage in each step.


 Step 1: 15% of battery voltage


 Step 2: 64% of battery voltage
Location of EGR valve EGR valve arrangement
Vacuum modulator 1 Connector (potentiometer)
Circuit of potentiometer
312

MUSSO-SPORTS 1A-9
SUPPLEMENT
Test Step 1: EGR operating range (between vacuum pump and EGR valve)
(Condition: at idling) Remove the vacuum modulator 1 and vacuum line (to the directionof vacuum pump), then installvacuum tester.
Check whether the vacuum pressure can be generated between vacuum modulator 1 and vacuum line (vacuum pump side).
Is the vacuum pressure of 900 mbar generated?
Is the vacuum pressure properly generated in the vacuum line between vacuum modulator 1 and EGR valve?
Check the EGR valve for leaks and sticking.
Remove the vacuum hose from outlet port (to the direction of vac-uum pump) of vacuum modulator.Connect the tester and checkwhether vacuum pressure changeor not when the engine rpmchanges. Install the tester into Inlet port of EGR valve and check whether thevacuum pressure changes or notwhen engine rpm changes.
1. Start the engine, then remove EGR valve hose with idling. If the valve disk snaps into position, EGR valve operates properly.
2. Install the T-connector into inlet port of EGR valve, then connects the manual vacuum pump and the vacuum tester in each connection.
3. Generate -700 mbar of vacuum pressure with manual vacuum pump. If EGR will not open (stay vacuum state), EGR valve should be replaced (due tosticks of inner valve guide and valve).Vacuum leaks from vacuum line
NO
Is the vacuum modulator 1 operated properly?

 Is the vacuum pressure varied
between 0 and 600 mbar?


 Is the constant vacuum pressure
generated in constant engine speed?
Check the battery voltage can be supplied to vacuum modulator 1through EGR control unit. With thebattery voltage supplied, check thevacuum pressure can be changedaccording to the accelerator pedalpositions. If the vacuum pressurecannot be generated or changed,the vacuum modulator should bereplaced.
NO
Vacuum modulator 1 has a problem in power supplying system.
NO
Replace the vacuum line between vacuum modulator 1 and EGR valve with new one.
YES YES
YES

1A-10 MUSSO-SPORTS
SUPPLEMENT
Test Step 2: Exhaust gas control mode with no-load sharp acceleration (between vacuum pump and ALDA)
Condition:
1. At idling, monitor the changesof boost pressure while changing the accelerator pedalposition slowly.
2. Remove the inlet port from ALDA on fuel injection pump,then install the pressure tester.
Before checking the generation of vacuum pressure, Check whether the boost
pressure from intake manifold can be applied to ALDA or not in the range beyond no-load sharp acceleration mode. Check whether the boost pressure can be generated between intake manifold and ALDA. Boost pressure at idling: approx. 5 ~ 7 mbar. While depressing the accelerator pedal slowly, does the boost pressure of 220 ~ 270 mbar generate at 4,000 ~ 4,500 rpm?
At idling, install the pressure tester into inlet port of vacuum modulator2 and read the negative pressure(specified value: approx. -900mbar) on tester. Install the vacuum tester into inlet port of solenoid valve, and checkwhether the negative pressure isgenerated in no-load sharp accel-eration mode or not, and read thechanges of vacuum pressurewithin specified ranges.
NO
If the boost pressure is not within specified value, appropriatepressure line should be replaced. Check the solenoid valve with the same method in no-load sharpacceleration mode.
YES
YES
Check the vacuum circuit in no-load sharp acceleration mode. Is the approx. -900 mbar of negative pressure generated between vacuum pump line and inlet port of vacuum modulator 2?
In vacuum modulator 2, check the vacuum circuit between inlet port and outlet port. Is the approx. -300 ~ 650 mbar of negative pressure generated in no-load sharp acceleration mode?
Check the vacuum circuit between outlet port of vacuum modulator 2 and inlet port of solenoid valve. Is the approx. -300 ~ 650 mbar of negative pressure generated in no-load sharp acceleration mode?
Install the vacuum tester into outlet port of vacuum modulator, andcheck whether the negativepressure is generated or not in no-load sharp acceleration mode.
Check the intake boost pressure by ranges


 Boost pressure line
between intake manifold and solenoid valve


 Boost pressure line
between ALDA and solenoid outlet valve
NO
Check the voltage supplying and vacuuming
Check whether the EGR control unit can supply the battery voltage tovacuum modulator 2. If can, in no-load sharp acceleration mode,check whether the negative pressuremay vary within specified ranges. Ifthere are not any vacuuming or if thenegative pressure will not be varied,replace the modulator with new one. YES
YES
NO
Replace the vacuum hose in the range.

MUSSO-SPORTS 1A-11
SUPPLEMENT
Install the vacuum tester into out- let port of solenoid valve, andcheck whether the negative pres-sure is generated in no-load sharpacceleration mode or not, and readthe changes of vacuum pressurewithin specified ranges.
YES
In solenoid valve, check whether the vacuum pressure is generated between inlet port and outlet port. When the power is supplied, does the solenoid valve close and the intake boost pressure cut off to complete the vacuum circuit?
NO
Replace the vacuum hose in the range.
Install the vacuum tester into out- let port of solenoid valve, andcheck whether the negative pres-sure is generated in no-load sharpacceleration mode or not, and readthe changes of vacuum pressurewithin specified ranges.
YES
Check whether the vacuum pressure is generated between outlet port of solenoid valve and inlet port of ALDA. Is the approx. -300 ~ 650 mbar of negative pressure generated in no-load
sharp acceleration mode?
NO
Replace the vacuum hose in the range.